JPH11332151A - Alternating current generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate treatment of the crossing parts between a plurality of lap wound parts, when multipolar construction to be required for an AC generator for vehicles is formed by lap winding, and to improve the productivity. SOLUTION: The wire rods of stator coils 16 of three phases, wound on a stator core having a plurality of teeth, are put in the grooves between the teeth. In a stator core, three teeth are arranged at every two magnetic pole pitches of a rotor in the circumferential direction, and only the stator coil of one phase from among the stator coils of three phases is wound in each tooth by lap winding, so that each phase of the stator coils 16 forms a pair to correspond. The stator coil 16 of one phase has a plurality of lap wound parts and a plurality of crossing parts which connect between the lap-wound parts. Accordingly, it is thermally advantageous, and reduced noise can be achieved. In addition, the crossing parts can be treated in a manufacturing process only at one end surface of the stator core, and the productivity is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a rotating electric machine, and is particularly suitable for use in an AC generator for a vehicle.

[0002]

2. Description of the Related Art Hitherto, an alternator for a vehicle has been required to have a higher output and a smaller size in accordance with an increase in the use of electric devices and electric control devices of the vehicle and a saving of mounting space. As a means for increasing the output of an alternator, a conventional one for improving the cooling efficiency is disclosed in, for example, JP-A-63-597.
As disclosed in Japanese Patent Publication No. 44-44, there has been known an improved cooling efficiency in which a gap is provided between stator coil groups to be wound, and a cooling fan is opposed to the gap to form a ventilation path. ing.

[0003]

However, according to the conventional stator coil winding structure of the AC generator for a vehicle, the three-phase coil is used in both the lap winding method and the wave winding method. Since the three-phase coils are wound around the three teeth of the stator core so that the three-phase coils surround the three teeth, the coils of the three-phase coils are overlapped and overlapped. There is a problem in that the length of the coil is extended, the amount of heat generated increases, and the thermal efficiency decreases.

[0004] For example, as shown in FIGS. 7 and 8, in a conventional motor, a stator 2 fixed to the inner peripheral wall of a cylindrical frame 1 has 32 teeth 3 having a T-shaped cross section arranged in an annular shape. Teeth 3 extend in the axial direction and protrude inward in the radial direction, and the coils x, y, X, y,
z is wound around each of the three teeth 3 as one unit, and the coils x, y, and z are wound around the teeth 3 in the X, Y, and Z phases.
Because it is wound according to the winding order of the phase, the lap winding method,
In any of the winding methods of the wave winding method, the coils x, y, and z have a wrap margin covering each other at both the axial front end and the axial rear end of the teeth 3, so that the coil length is increased and The exposed area of the coil was reduced and the area of contact with the outside air was reduced, so that the cooling effect was insufficient.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, in which a stator coil is formed by lap winding in an automotive alternator, and a multi-pole structure required for an automotive alternator is wrapped. It is an object of the present invention to provide a vehicular alternator that is easy to process at a crossover portion between a plurality of lap winding portions and is excellent in productivity even when formed. SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicular alternator that can easily process a crossover portion and a drawer portion disposed at an end of a stator and is excellent in productivity.

[0006]

The present invention employs the following technical means to achieve the above object. In the present invention, a rotor having a plurality of magnetic poles, a stator core formed with a plurality of teeth, and a three-phase stator coil wound around the stator core are provided, and a wire of the stator coil is disposed between the teeth. In the automotive alternator housed and wound in the groove, the stator core is provided with three teeth in a circumferential direction for each two magnetic pole pitches of the rotor, and each tooth is provided with a pair of each phase of the stator coil. Only one of the three-phase stator coils is wound by lap winding on each tooth, and the one-phase stator coil has a plurality of lap winding portions. And a plurality of bridging portions connecting the overlapping winding portions, and the plurality of bridging portions are arranged only at one end of the stator core. Adopt the technical means of the automotive alternator, characterized in that there.

In such a configuration, since the stator coil is formed by lap winding, a thermally advantageous configuration is provided and low noise can be realized. Further, since the plurality of transition portions connecting between the plurality of overlapping winding portions are arranged only on one end face of the stator core, the processing of the transition portion in the manufacturing process can be performed only on one end face of the stator core, and Can be enhanced. In addition, the configuration required for arranging the plurality of transition portions can be arranged corresponding to only one end face of the stator core, and the configuration as a vehicle AC generator can be simplified and downsized.

[0008] It is preferable that the stator coil has a drawer portion, and the drawer portion and the plurality of transition portions are both disposed only at one end of the stator core. Can be. According to such a configuration, both the drawn-out portion and the transition portion of the stator coil extending in the axial direction can be processed on one end face of the stator core. Further, it is possible to adopt a configuration in which all of the plurality of transition portions included in the three-phase stator coil are arranged only at one end of the stator core.

According to the present invention, there are provided a rotor having a plurality of magnetic poles, a stator core formed with a plurality of teeth, and a stator coil wound around the stator core.
In a vehicle alternator in which a wire of the stator coil is housed and wound in a groove between the teeth,
The number of inter-teeth grooves of each pole and each phase is set to 0.5, and the stator coil is wrapped around the teeth, and the stator coil of each phase is provided with a plurality of lap winding portions and the lap winding. And a plurality of crossover portions for connecting between the portions, wherein a plurality of the crossover portions are disposed only at one end of the stator core. .

In such a configuration, since the stator coil is formed by lap winding, a thermally advantageous configuration is provided and low noise can be realized. Further, since the plurality of transition portions connecting between the plurality of overlapping winding portions are arranged only on one end face of the stator core, the processing of the transition portion in the manufacturing process can be performed only on one end face of the stator core, and Can be enhanced. In addition, the configuration required for arranging the plurality of transition portions can be arranged corresponding to only one end face of the stator core, and the configuration as a vehicle AC generator can be simplified and downsized.

It is to be noted that the stator coil has a drawer portion, and the drawer portion and the plurality of transition portions are both arranged only at one end of the stator core. Can be. According to such a configuration, both the drawn-out portion and the transition portion of the stator coil extending in the axial direction can be processed on one end face of the stator core. Further, it is possible to adopt a configuration in which all of the plurality of transition portions included in the stator coil are disposed only at one end of the stator core.

[0012] The present invention provides a rotor having a plurality of magnetic poles,
A vehicle having a stator core formed with a plurality of teeth and a multi-phase stator coil wound around the stator core, wherein a wire of the stator coil is housed and wound in a groove between the teeth. In the AC generator, each phase of the stator coil is wound around the teeth of the stator core by lap winding without sharing the teeth with each other to form a plurality of fixed magnetic poles, One fixed-side magnetic pole of each phase is arranged within a range of two magnetic pole pitches of the rotor, and the stator coil further includes a plurality of lap winding portions and a plurality of crossover portions connecting between the lap winding portions. And a plurality of the crossover portions are disposed only at one end of the stator core. That.

In such a configuration, since the stator coil is formed by lap winding, a thermally advantageous configuration is provided and low noise can be realized. Further, since the plurality of transition portions connecting between the plurality of overlapping winding portions are arranged only on one end face of the stator core, the processing of the transition portion in the manufacturing process can be performed only on one end face of the stator core, and Can be enhanced. In addition, the configuration required for arranging the plurality of transition portions can be arranged corresponding to only one end face of the stator core, and the configuration as a vehicle AC generator can be simplified and downsized.

[0014] It is preferable that the stator coil has a drawer portion, and the drawer portion and the plurality of transition portions are both disposed only at one end of the stator core. Can be. According to such a configuration, both the drawn-out portion and the transition portion of the stator coil extending in the axial direction can be processed on one end face of the stator core. Further, it is possible to adopt a configuration in which all of the plurality of transition portions provided in the multi-phase stator coil are disposed only at one end of the stator core.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of an automotive alternator according to the present invention will be described with reference to FIGS. First, the structure of the generator will be described with reference to FIG. 3, and then the winding structure of the stator coil will be described in detail.

Referring to FIG. 3, a stator 14 comprising a stator core 15 and a stator coil 16 wound around the front core 12 and the rear frame 13 is fixed on the inner periphery of the front frame 12 and the rear frame 13 which are fixed to each other by bolts 10 and the like. Fixed.

A rotor coil 17 for generating an electromotive force in the stator coil 16 by electromagnetic induction is wound around a metal bobbin and is fixed by being sandwiched between a pair of pawl cores 18 and 19. A shaft 20 for mechanically fixing the pole cores 18 and 19 is rotatably supported by bearings 21 and 22. These bearings 21 and 22
The cylindrical bearing boxes 23, 24 to which are mounted
Are the front frame 12 and the rear frame 13, respectively.
It is attached to the center of the side of the camera.

A pulley 25 to which rotational driving force from an engine (not shown) is transmitted is connected to a front end of the shaft 20 by a nut 2.
6 and a washer 27. A conductor 30 is connected to the rotor coil 17 at the rear end of the shaft 20.
Slip rings 31 and 32 electrically connected via
Are mounted outside the rear frame 13.

On both sides of the pole cores 18, 19, cooling fans 34, 3 having a diameter smaller than the inner diameter of the stator are provided.
5 is concentric with the shaft axis, and the respective fan blades are fixed toward the axial front and rear of the pole cores 18 and 19, respectively. Cooling fan 34,
Reference numeral 35 has a diagonal flow shape which is inclined in the rotor rotation direction so as to form a cooling air passage for cooling the rotor coil 17 and the stator coil 16. A suction window 37 for sucking cooling air into the generator is formed near the bearing 22 and at a position facing the cooling fan 35. Further, a discharge window 38 for discharging the cooled hot air is formed in the front frame 12.

Next, the winding state of the stator coil 16 will be described with reference to FIGS. 1, 2 and 4. FIG. The stator core 15 has an annular shape, and has a cross section T
A plurality of tooth-shaped teeth 41 project at predetermined intervals. The stator coil 16 is wound around a groove between the teeth formed between the adjacent teeth 41. The three-phase coils x, y, and z of the stator coil 16 are wound around mutually different inter-tooth grooves, and at each inter-tooth groove, as shown in FIG. 1B, x, y, y, z, and z.
And x coils are divided and distributed and wound in two layers. The number of the teeth 41 is three teeth 41 per two magnetic pole pitches of the magnetic poles formed by the rotor coils inside the pole cores 18 and 19 radially inside the teeth 41.
a, 41b, and 41c are formed, and the teeth 41 whose total number is three times the number are formed in an annular shape.

The winding method of the stator coil of this embodiment is of the lap winding type, and the winding sequence of the three-phase coils is as follows. First, as shown in FIG. 2, after winding the X-phase coil x around the teeth 41a, the adjacent teeth 41b,
Wrapping is performed around the next tooth 41a at an interval of 41c, and then winding is repeated in the same manner at intervals of two teeth 41b and 41c. After winding the X-phase coil x, the Y-phase coil y is wound around the teeth 41b, and then the Y-phase coil y is wound around the adjacent teeth 41b with the two teeth 41c and 41a being spaced from each other. Similarly, the Y-phase coil y is wound in an annular shape. After the winding of the Y-phase coil y, the Z-phase coil z is wound around the tooth 41c, and then the Z-phase coil z is wound around the next adjacent tooth 41c with two teeth 41a and 41b spaced apart. Thereafter, winding is repeated in the same manner.

The stator coil 16 wound in this manner is, as shown in FIGS.
An X-phase coil x is wound around the groove between the teeth between 1a and 41b, and a Y-phase coil y is wound around the groove.
The Y-phase coil y is wound around the groove between the teeth b and 41c, and the Z-phase coil z is wound around the shallow groove.
An X-phase coil x is wound around the groove between c and 41a in the groove deep portion, and a Z-phase coil z is wound in two layers in the groove shallow portion. X-phase, Y-phase, and Z-phase coils x, y, and z are:
The teeth 41a, 41b, and 41c are wound around the respective teeth by lap winding.

According to the winding structure of the stator coil,
As shown in FIG. 4, gaps A and B having unequal sizes are formed between the front end 16a and the rear end 16b of the wound coil of the stator coil 16, respectively. When the gaps A and B are formed, the gaps serve as passages for the cooling air, and the cooling effect is increased by an increase in the exposed area of the coil for cooling air contact formed by the gaps.

According to the configuration described above, three teeth 41a, 41b, 41c are provided at equal intervals on the inner periphery of the stator core 15 between the two magnetic pole pitches of the rotor coil, and these teeth 41a, 41b, 41c are circular. Since the X-phase, Y-phase, and Z-phase windings are sequentially arranged in the grooves between adjacent teeth in a ring shape, three-phase electromotive force is generated in the X-phase, Y-phase, and Z-phase coils. In the case of this stator coil winding structure, the winding pitch is 2/3 magnetic pole pitch, so that the resistance value of the total coil length per phase is 2 / compared to the conventional stator coil winding structure in which the pitch is one magnetic pole. 3
The loss that occurs when the same load current flows is (current I)
² (Resistance R), it is reduced to about 67%, the amount of heat generation is reduced, and the rate of temperature rise is reduced.

Further, comparing the conventional example in the case of the lap winding method and the present embodiment with reference to FIG. 5, the coil of the present embodiment can be dividedly wound in the circumferential direction.
In the case of the conventional winding method, a lap portion L1 is formed between the X, Y, and Z phases. Therefore, in the present embodiment, since the wrap portion of the multi-turn coil does not basically occur, the ratio of the exposed area of the cooling air contact per the entire length of the coil is increased. By applying cooling air to both ends of the coil by the provided cooling fans 34 and 35, the cooling effect is improved.

Further, in this embodiment, as shown in FIG. 1, the gap length between the pole cores 18, 19 and the teeth 41a, 41b, 41c of the stator core 15 is larger than the core claw central portion 19a. Since the end 19b is formed in a concave shape, the gap length D is larger than the gap length C shown in FIG.
Is increased, the vortex of the cooling air generated by the cooling fans 34 and 35 is generated, the cooling performance of the pole cores 18 and 19 and the surface of the stator core 15 is improved, and the ventilation is improved. A cooling air release effect is produced at the front end and the rear end of the coil, and the cooling performance of the front end and the rear end of the coil is further improved. Since the cooling air passage having the gaps A and B, the gap length C, and the gap length D is formed, the ventilation is improved, and the ventilation property is remarkably improved. large. Further, since the sizes of the gap A and the gap B are unequal, pitch noise (monochromatic frequency component wind noise) due to the cooling fan wind pressure is not likely to occur.

As described above, according to the power generator according to the embodiment of the present invention, cooling is effectively performed by increasing the exposed area of the stator coil, and the same number of turns can be achieved by using a coil having a shorter overall length than before. Furthermore, since the coil is wound in two layers in the groove between the teeth, the leakage winding of the coil is halved, and the leakage reality is halved, so that a sharp rising output characteristic from a low speed to a medium speed or a high speed can be obtained. Further, the ratio of the area of the inner diameter of the stator facing the iron portion is increased, the gap permeance is somewhat reduced, the magnetic flux is increased, and the low-speed output is increased. Further, since the number of teeth is halved from that of the conventional one, the 36th order of the main component of the magnetic sound is greatly reduced or the frequency is not unpleasant. Further, there is an effect that the magnetic flux pulsation frequency on the magnetic pole surface is halved and the eddy current loss is reduced to １ ／.

The winding state of the stator coil in this embodiment will be described with reference to FIG. The X-phase stator coil includes a plurality of lap winding portions X11, X12, X13,. Between these, a plurality of crossover portions X21, X22 ...
Connected by All of the plurality of crossover portions X21, X22,... Belonging to one phase are arranged only on one end face of one stator core as shown. X
The phase stator coil has a lead portion X31. The drawer portion X31 includes a plurality of crossover portions X2.
1, X22,... Are arranged only on one end face of the stator core.

The Y-phase stator coil has a plurality of lap winding portions Y11, Y12... Y1n. Between these,
Are connected by a plurality of crossover portions Y21, Y22. The plurality of transition portions Y21 and Y22 belonging to these one phase
Are arranged only on one end face of one stator core as shown. The Y-phase stator coil has lead portions Y31 and Y32. The drawer portions Y31 and Y32 are made up of a plurality of crossover portions Y21,
Are arranged on only one end face of the stator core together with Y22.

The Z-phase stator coil has a plurality of lap winding portions Z11, Z12... Z1n. Between these,
.., Z2n. A plurality of transition portions Z21, Z belonging to these one phase
All of 22... Z2n are arranged only on one end face of one stator core as shown. The Z-phase stator coil has lead portions Z31 and Z32. These lead portions Z31 and Z32 are arranged only on one end face of the stator core together with the plurality of transition portions Z21, Z22... Z2n.

As described above, all of the plurality of transition portions of the three-phase stator coil as the multi-phase stator coil are arranged only on one end face of the stator core. In addition, all of the plurality of lead wires are arranged on only one end face together with all the transition portions.

(Second Embodiment) FIG. 6 shows a second embodiment of the present invention. The second embodiment shown in FIG. 6 is an example in which the present invention is applied to an internal fan type, in which a cooling fan 50 is provided in front of the stator coil 16.

In the first embodiment shown in FIG. 3, the positions of the cooling fans 34 and 35 are provided inside the radial direction of the stator coil 16, but in the second embodiment shown in FIG. The cooling fan 50 is provided on the front side.
That is, in the second embodiment, the front cooling fan 50
Is fixed to the front end side surface of the pole core 18, the cooling fan mounting position is inside the front diameter of the stator coil 16, and the fan blade tip 50 a extends forward in front of the stator coil 16 and further radially outward. Since the cooling air flows mainly in the direction of arrow E by the cooling fan 50, the cooling effect is further increased in combination with the above-described stator coil winding structure having a large cooling air contact area of the stator coil 16. is there. In FIG. 6, the same reference numerals are given to components substantially the same as those shown in FIG.
Description is omitted.

[Brief description of the drawings]

FIG. 1A is a schematic configuration diagram showing a part of a winding state of a stator coil according to an embodiment of the present invention, and FIG. 1B is a schematic diagram showing a cross section of a stator coil wound in a groove between teeth of a stator core. It is sectional drawing.

FIG. 2 is a developed view of a coil winding showing a winding state of a stator coil.

FIG. 3 is a cross-sectional view illustrating an AC generator.

FIG. 4 is a partially developed external view of the stator shown in FIG. 1;

FIG. 5 is an explanatory diagram for comparing and explaining a conventional example using a lap winding method and an example according to an embodiment of the present invention.

FIG. 6 is a partially cutaway sectional view showing an AC generator according to a second embodiment of the present invention.

FIG. 7 is a front view showing a conventional stator.

FIG. 8 is an enlarged view of a portion IX shown in FIG. 7;

[Explanation of symbols]

 14 Stator 15 Stator core 16 Stator coil 17 Rotor coil 18, 19 Pole core 20 Shaft (rotor) 41 (41a, 41b, 41c) Teeth x X-phase stator coil y Y-phase stator coil z Z-phase stator coil

Claims (9)

[Claims] 1. A stator having a plurality of magnetic poles, a stator core having a plurality of teeth formed thereon, and a three-phase stator coil wound around the stator core, wherein a wire of the stator coil is disposed between the teeth. In the alternator for a vehicle, which is housed and wound in the groove of (3), three teeth are arranged on the stator core in the circumferential direction for two magnetic pole pitches of the rotor, and each phase of the stator coil is provided in each tooth. Only one phase stator coil of the three-phase stator coils is wound on each tooth by lap winding so as to correspond to each other as a pair, and the one-phase stator coil is formed by a plurality of lap windings. And a plurality of bridging portions connecting the overlapping winding portions, and the plurality of bridging portions are arranged only at one end of the stator core. Automotive alternator, characterized by that. 2. The stator coil according to claim 1, wherein the stator coil has a lead portion, and the lead portion and the plurality of transition portions are both disposed only at one end of the stator core. Item 7. The vehicle alternator according to Item 1. 3. The alternating-current power generator for a vehicle according to claim 1, wherein all of the plurality of crossover portions provided in the three-phase stator coil are arranged only at one end of the stator core. Machine. 4. A rotor having a plurality of magnetic poles, a stator core formed with a plurality of teeth, and a stator coil wound around the stator core, wherein a wire of the stator coil is provided in a groove between the teeth. In the vehicle alternator that is housed and wound, the number of inter-teeth grooves of each pole and each phase is 0.5, and the stator coil is wound around the teeth in an overlapping manner. The stator coil has a plurality of lap winding portions,
An alternator for a vehicle, comprising: a plurality of bridging portions that connect the lap winding portions; and the plurality of bridging portions are arranged only at one end of the stator core. 5. The stator coil according to claim 1, wherein the stator coil has a drawer portion, and the drawer portion and the plurality of transition portions are both disposed only at one end of the stator core. Item 7. The vehicle alternator according to Item 4. 6. The alternator for a vehicle according to claim 4, wherein all of the plurality of transition portions provided in the stator coil are disposed only at one end of the stator core. 7. A rotor having a plurality of magnetic poles, a stator core having a plurality of teeth formed thereon, and a multi-phase stator coil wound around the stator core, wherein a wire of the stator coil is disposed between the teeth. In the automotive alternator housed and wound in the groove portion, each phase of the stator coil is wound by lap winding with respect to the teeth of the stator core without each phase sharing the teeth with each other. To form a plurality of fixed-side magnetic poles, one fixed-side magnetic pole of each phase is disposed within a range of two magnetic pole pitches of the rotor, and further, the stator coil has a plurality of lap winding portions, A plurality of bridging portions connecting the overlapping winding portions, wherein the plurality of bridging portions are arranged only at one end of the stator core. That AC generator for a vehicle. 8. The stator coil according to claim 1, wherein the stator coil has a lead portion, and the lead portion and the plurality of the transition portions are both disposed only at one end of the stator core. Item 7. An automotive alternator according to Item 7. 9. The vehicle AC power generator according to claim 7, wherein all of the plurality of transition portions provided in the plurality of stator coils are disposed only at one end of the stator core. Machine.